1. ADSL Advanced Testes DLT2

DLT2 Series ADSL handheld tester offers helpful features for the technician in

installation, maintenance, and troubleshooting phases of ADSL service deployment. Along with the tester, in office ADSL Line Specialist software provides powerful data management and analysis function on data collected from site operation.

With built-in Li-lon chargeable battery, DLT2 supports more than four hours continuous working as a right-hand tool for ADSL site measuring and service acceleration.


  • Integration of simulation test, cable test and higher layer protocol test.
  • ISP login simulation test to verify user login process.
  • Golden modem replace mode, simulate user's ADSL modem.
  • Managing the test results in project mode, easy data mining and query.
  • User friendly interface to enhance operation efficiency.
  • Online software upgrade via Email or website.

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  • IITU-T G.922.1 <<Asymmetric digital subscriber line (ADSL) transceivers>>
  • IITU-T G.922.2 <<Splitterless asymmetric digital subsriber line (ADSL) transceivers>>
  • IANSI T1.413

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DLT2 provides 3 main test functions aiming at common defects in ADSL network on the mark, which provides various testing testing items to solve customers trouble such as activation failure, login failure, low data transmission rate and regular off line

  • ADSL Service Simulation Test, to facilitate subscriber activation and shoot ADSL trouble by key performance indicators measuring
  • ADSL Cable Test, to identify eligibility of physical layer of subscriber line
  • Higher Layer Protocol Test, to estimate usage of subscriber from application layer view

Line parameter measurement
Maximum line rate, actual rate, actual work channel (fast or interleaving), channel usage, current noise margin, line attenuation, TX power and manufacture serial number and version number of office terminal equipment ( upstream / downstream )

ADSL line error code analysis
ADSL line error code duration, severe error code duration and unusable connection duration, Loss of Signal (LOS) count, LOS duration and LOS ratio etc.

ADSL alarm event statictics
Forward Error Corrections (FEC), Cyclic Redundancy Check (CRC) and Header Error Check (HEC) at both the near end and the far end.

DMT sub-channel carrier chart
Displaying bit-map of DMT modulated sub-channel in and detailed numerical value

Loop resistance measurement / line length estimation
Measuring loop DC resistance and calculate line length according to cable gauge.

Line voltage measurement
Measuring DC voltage of subscriber line

ADSL Modem Simulation
In place of ADSL Modem, displaying real-time upstream and downstream byte rate; recording maximum data rate.

ISP login test
Simulating PPPOE virtual dialing user behavior by inputting VPI, VCI, username and password to validate user login by PPPOE virtual dialing mode

Sending consecutive PING packets to a certain host to validate connectivity of WAN and displaying error rate in testing process.

LAN test
Using embedded Ethernet port to connect to Ethernet switch and sending PING packets to validate connectivity of LAN

Frequency domain attenuation measurement
Do the test with two testers. One TX tester sends testing (0Hz - 1.1MHz), and the RX tester receives testing signal, display signal attenuation of every DMT sub-channel frequency in graphic or value when mouse-on

Broadband noise measurement
With built-in IEEE G weighting filter(frequency range: 20kHz-1,1MHz), the tester provides interferential signal intensity testing of subscriber line and presents reference value for user to validate minimum rquirement of ADSL service installation.

Power Spectrum Density (PSD) measurement
Displaying intensity of interferential signal and cross-talk from adjacent channel on every frequency within ADSL frequency band in graphic.Employing the most advanced DSP technology, it takes only 2 seconds for DLT2 to simultaneously detect spectrum density of 255 DMT tone in parallel.

Longitudinal Balance Test
Do the test with two testers. One tester sends testing signal within ADSL frequency range, and the other tester receives testing signal and display longitudinal balance attenuation value of every frequency within ADSL frequency band to validate symmetry of tested line.

Cross Talk (NEXT/FEXT) Testing
Do the test with two testers. One tester sends testing signal within ADSL frequency band, and the other tester receive testing signal and display NEXT/FEXT index of tested cable in graphical format.

Testing Data Management & Analysis
DLT2 series ADSL tester can hold all testing data from 240 tested lines in NAND FLASH chip. User can query historical testing data by 'File Management' menu on the tester or send testing data to PC via RS232 cable for further detailed analysis by 'Testing Data Management System' to satisfy requirement of ADSL line maintenance technician.

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Dimensions 240 mm x 110 mm x 45 mm  
Weight 0.8 kg
Testing Interface RJ45, RJ11, RJ9
Power Mode Outer Power AC 220V +/- 10% 50Hz +/- 5 %
Built-in Battery Li-ion rechargeable
Battery Features Battery Model 4 Li-ion chargeable batteries
Charging Time 2-3 hours, no memory effect
Ready Time 3-4 hours
Display Size 60 mm x 40 mm
Resolution 320 x 200 pix
Others Single color, background light
Working Environment Temperature -5C ~ +45C
Humidity < 90 %
Communication RS232 RS232, DB9 Female
10Base-T 10Base - T, RJ45
Data Storage Storage Capability 32Mbyte Flash
Storage Quantity Testing data of 240 subscriber lines
Standard Environment GB6587-86
Modulation DMT
ADSL ANSI T1.413 / ITU-T G.922.1 / ITU-T G.922.2
Higher Protocol TCP/IP / RFC2516 (PPPoE) / RFC 1483 ( bridge )
Resistance Measurement Range 0 - 10M Ohm
Precision +/- 7% (0-10Ohm)
+/- 5% (10-10M Ohm)
Voltage Measurement Range DC -200V ~ +200V
Precision +/- 7% (-10V ~ +10V)
+/- 5% (+/- 10 V ~ +/- 200V)
PSD Measurement Range -126dBm/Hz ~ -16.36dBm/Hz ( frequency: 8KHz ~ 1100KHz)
Precision +/- 1 dBm/Hz
Broadband Noise Measurement Range 0 ~ -110 dBm
Precision +/- 1 dBm
Frequency Range 20kHz ~ 1.1 MHz (IEEE G weighting filter)
Frequency Domain Attenuation Measurement Range 0dB ~ -90dB ( Frequency : 8KHz ~ 1100 KHz )
Precision +/- 1 dB
Crosstalk Measurement Range 0 dB ~ -90dB ( Frequency : 8KHz ~ 1100 KHz )
Precision +/- 1 dB
Longitudinal Balance Measurement Range 0dB ~ -90dB ( Frequency : 8 KHz ~ 1100 KHz )
Precision +/- 1 dB

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